Pages

Tuesday, 27 October 2015

The Accuracy of Fuzzy

Strange, but the old
and well worn adage that “there are three types of lie; lies, damned lies, and
statistics” (apocryphally ascribed to Benjamin Disraeli but certainly quoted by
Mark Twain) seems to be universally acknowledged by all; in a jolly jocular,
chatting down-the-pub sort of way but is not actually considered and accepted
as a fundamental truth.

Some time ago (here we
go again – but I shall continue!) I read an excellent piece about
Climate Change. Not “Global Warming” mind, but “Climate Change”. I wish I could
remember where I read it because it was a careful piece of scientific writing
couched in terms that as a non-scientist I could understand and that laid out its thesis in a succinct and even handed manner. The
publishing platform for this piece of work must have been some open-access
forum and was probably linked from the Guardian, the BBC, Al Jazeera or some
similar notable news channel. In common with such publications there was ample
opportunity for the man-in-the-street to comment – and given the subject matter
comments abounded and re-bounded with lots of energy.

I should add that the
piece in question supported the thesis that we are experiencing climate
change and that on balance that change could be attributed to anthropogenic influences. The comment that attracted my attention most was from some Colonel Blimp from
Stoke Poges, or perhaps he was a Parish Councilor from Upper Twittering;
either way he sadly slotted into a stereotype that one knows still exists but
wished it didn’t. This Gentleman clearly had time on his hands and was either bored or angry (I suspect that
latter) because he wrote that he had read the piece, printed it out and re-read
it and marked with a highlight pen all references to uncertainty. So words or
phrases such as “on balance”, “it would appear”, “subject to further data”,
“uncertain”, “less certain”, “requires further study”, and so forth and so on
were subjected to his damning scrutiny. If I remember correctly (and I do wish
I had saved the piece) he even reported on the number of such apparent
vacillations or violations of certainty. He justified this pointless exercise
by concluding that a scientific article redolent with so many uncertainties was
unworthy of publication and was essentially very poor science.

Staggered by this
fat-headed critique I returned to the offending article and re-read it to see
if I had missed anything, and concluded that I had not. The author had presented
his thesis. He examined the evidence and admitted the strengths and weaknesses of
his thesis in this context, and came to a reasoned conclusion. To me he had
presented the reader with very good science that admitted to significant
levels of uncertainties in a field of study that is rotten with doubts.

The very essence of
science had been missed by the misguided commenter who had clearly approached
the subject with a raft of boiler-plated preconceptions that he did not wish to
have dented, let alone breached. The author of the offending article had in my
view actually presented good science with a humility that spoke not of
uncertainty but rather of assurance that there is no certainty. Science with
honesty; an honesty borne of reservation.

Aside from this
laughable example of self-inflicted misinformation there are the far more
sinister examples of deliberate obfuscation by apparent experts who lift large
amounts of often pseudo scientific information to use as contrary arguments
against scientific standpoints. In these instances the nay-sayer is more often
than not in the pay of the beneficiaries of the contrary view. A superb recent
example occurred in the South African debate about wind power and other forms
of alternative energy. The Nay-sayer used selective evidence and extrapolated
no doubt valid statistics but stretched them to breaking point in order to make
his point. In this instance both accepted doubts and selective anecdotes
were brought to bear to rubbish the entire alternative energy industry. A
little bit of judicious digging uncovered the fact that the author of this
clumsy piece of writing was in fact a retired PR person for one of the
multinational oil companies, no doubt working on enhancing his pension by
“consulting” to the industry on the murky affairs misinformation.

Incidentally I use the
word clumsy advisably here, because unless you were alert to the possibility of
a bit of wholesale wool pulling over the eyes the entire article could have been
taken at face value by the unsuspecting and uninformed reader. Indeed the
danger of uncritical acceptance of this type of underhand journalistic guerilla
warfare (which was actually op ed stuff) was evidenced by the piece in question
- because it was published wholesale (in the business section nogal) and without comment by a
respected South African Sunday Newspaper. Only those who were incensed by the
obvious bias and factoid cherry picking took the article to task, and of course
this type of debate and debunking
inevitably happens on subterranean comment pages that are hidden from the
general public just below the pavement level of the web.

Which leads me effortlessly
to the realms of the pavement - that area inhabited by the gutter press,
where individual and often of singular facts are pedaled to marvelous levels of
crassness.

The UK Mail on Sunday
fell unwittingly into a statistical crevasse by reporting that the extent of arctic
sea ice actually grew in 2013 contrary to trends predicted by climate
scientists. This, so the theory went, thus
disproved the doomsday prognostications of said scientists and therefore lent
weight to the climate change contrarians. This piece of factoid cherry picking was
gleefully picked up by the Guardian Online who could hardly contain themselves as
they hacked into the offending piece of journalism and with almost unseemly joy
pointed out that the other organ of right wing fat-headedness, the UK Telegraph, was
also guilty of this daft piece of inaccuracy.

The Guardian article
pointed out the very great danger of taking selective facts that have but short
term relevance and applying them to a longer time frame. Indeed, the extent of sea
ice had increased from one year to the next, however the thickness of the ice
was significantly reduced, and given the extreme losses of previous years this
increase, in the context of longer time frames was to be (and had been)
expected. The article directs the reader to the concept of “Regression towards the
Mean” which crudely says that if you’ve had extremes within a set of results
there is a reasonable expectation that future results will trend towards the
average and be therefore considerably below currently experienced extremes.

Or to put it another
way an apparent single extreme event now is no indication of a trend but has to
be seen in the context of all other valid data. And that, to my mind, as a
non-scientist, is where good science sits.

I might add that within
the “science” of environmental assessment is embodied the wonderful philosophy
of the “Precautionary Principle” which says that if there is any doubt, then err on the side of caution. This I
think is a sweeping acknowledgment that there is an awful lot out there that we
really do not understand. Statistics can be an invaluable guide, but must be
read in the context of a grand framework the extent and complexity of which I
don’t believe we have fully grappled with, let alone understood.

A statistic on its
own, without context, is a lie, because it tells a selective story. Without a
barrel load of statistics (and our world is so diverse and complex that we don’t
have that barrel load) we must rely upon imagination and intuition – a fuzzy
logic, and that’s the best we have.

Yorick - a sage (and a cat) who lives by his
wits and fuzzy logic.

I must say that every time
I am assailed by statistics I figuratively stand back and try to contextualize them
within my understanding of the world before I heard this new
information. Try it. It’s a liberating feeling because you can then apply your
own fuzzy logic and avoid the extremes of emotion that the purveyors of much of
these selected facts want you to experience; more often than not to feed their
own ends.